If the insert didn't get ripped out too badly, try the next bigger size screw.
If the hole is too big from the old screw ripping out, try 2 smaller screws in an X inlined with the 4 hole plastic insert.

I had good luck by squirting some super glue gel into the hole, then inserting the same screw, but not super tight. Later when the gel cures you can tighten it more. This, however, is for a hole that I don't need to change very often.

On my JP Magic Ride the inserts were plastic, maybe polypropylene, which epoxies and super glue will not bind to, but on my Goya Bolt they feel/sound like fiberglass reinforced epoxy. So first figure that out what your inserts are made of before trying to fix. If they are glass/epoxy use a thickened epoxy like WestSystems SixTen, want an epoxy with an adhesive thickener, and then your repair will be permanent. For epoxy I like your idea of wrapping screw in teflon tape, do not want grease mixing with epoxy as you screw it in. Just allow epoxy to cure before removing screw, otherwise will creat air bubbles when removing screw. If you do use epoxy, give WestSystems a call, their tech support is really knowledgable and helpful. Just make sure the screw hole is clean and dry before doing anything, maybe use isopropanol and a hair dryer and Q-tip.

Of all the suggestions here, the one I like the best is the whipper snipper line. We yanks call it weed whacker line. I think that is a better solution than my superglue gel.

By the way, the line is also great for installing harness rope through clear tygon tubing. Run the line through, press a small hook into the end, hook the hook to the harness rope, and pull.